In the strictest definition of the term, no.
Pedophilia [http://en.wikipedia.org/wiki/Pedophilia] is the attraction to prepubescent children (pre-teens), and usually includes a minimum five year age difference. This is the main issue and understanding of it.
Ephebophilia [http://en.wikipedia.org/wiki/Ephebophilia] is the (preferrential) attraction to teens after they've gone through puberty, specifically later-adolescence. This case is generally not considered a major issue, and can be argued to actually be somewhat reasonable (if not normal).
Legally speaking however, there may not be much difference; if someone is below the age of consent and the other is not, there's a problem. "Romeo & Juliet" laws do give this some lee-way (usually by a matter of reasonable age differnce). Still, they do get treated differently in the legal setting. Pedophiles are labelled as potential predators & repeat offenders, and are usually subject to monitoring long after they've done their time; there's usually a good reason for this too. Ephobpilia cases tend to fall under either "jail bait" or "abuse of power", there's probably plenty of "victimless crime"-type situations under this label too. Being attracted to a teen is fine (and that could be called the general opinion), but acting on it (especially when in position of power & authority, such as being a teacher) is where the trouble starts; the teen in question might even give full consent, but it's illegal for a reason (abuse of power is probably the main thing).
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Petite, slender, and/or less "gifted" women can bear a physical resemblance to your average teen and seem much younger than they actually are. How about considering the other side of the debate? Those ladies probably don't want to be ostracized/neglected solely because they appear "too young", and I haven't heard of any cases where that's actually happened. That and we can probably safely assume that particularly extreme cases, where the woman is an adult but has the body of a pre-teen, is almost always from the realm of fantasy.
Accounting for the full range of differences in the female anatomy, and twice as much for individual tastes... well, there should be no problem. Legality not being an issue and consent being given, people should be able to act accordingly. Not that it can't prevent strange situations and the pushing of social norms, but you're never going to be able to put a stop to some people just be plain wierd.
In other words, a relationship between a 100+ year old man and a petite 18-20 year old woman (and to up the ante, looks younger than that) can still be loving & intimate. There's plenty of reason to be suspect of the situation; but while improbable, it is still possible. Very wierd and probably requiring heavy assistance from the magic blue(?) pill, but possible.
Just try not to think about it too much.... oh damn. No! Why! Can't... avert... mind's... eye...
Pass the brain bleach! [http://tvtropes.org/pmwiki/pmwiki.php/Main/BrainBleach]